Field of the Invention
The present invention relates to a substrate processing apparatus.
Description of Related Art
Substrate processing apparatuses are used to subject substrates such as semiconductor substrates, substrates for liquid crystal display devices, substrates for plasma displays, substrates for optical discs, substrates for magnetic discs, substrates for magneto-optical discs, substrates for photomasks and other substrates to various types of processing.
In the substrate processing apparatus, a processing liquid is supplied to a main surface (an upper surface) of the substrate rotated by a spin chuck, for example. A splash prevention member is provided to surround the substrate held by the spin chuck. The processing liquid, splashed from the substrate, of the supplied processing liquid is received by the splash prevention member. At this time, splashes and a mist of the processing liquid splashed from the substrate may adhere to a back surface (a lower surface) of the substrate.
In a rotary main surface treatment apparatus described in JP 3-175617 A, a circular current member having an inclined current surface is provided below the spin chuck. Further, an outer cup is provided to surround a splash prevention cup (a splash prevention member). A divert path for letting a flow of gas flow from above is formed between the splash prevention cup and the outer cup. The divert path communicates with a space between the back surface of the substrate held by the spin chuck and the inclined current surface of the current member.
In this case, the gas flowing between the splash prevention cup and the outer cup due to a downflow of gas in the processing chamber is led to the space between the back surface of the substrate and the inclined current surface of the current member through the divert path. The led gas flows from the center of the substrate towards the peripheral edge of the substrate below the substrate. Thus, splashes and a mist of the processing liquid are prevented from flowing to the back surface side of the substrate.